20%NaOH,Δ20 \% \mathrm{NaOH}, \Delta20%NaOH,Δ
Na,C2H5OH,Δ\mathrm{Na}, \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}, \DeltaNa,C2H5OH,Δ
HCl+NaNO2,Δ\mathrm{HCl}+\mathrm{NaNO}_{2}, \DeltaHCl+NaNO2,Δ
Na2O\mathrm{Na}_{2} \mathrm{O}Na2O